The dynamics of the oxidant-antioxidant balance in the early phase of human acute biliary pancreatitis.

BACKGROUND/AIM Reactive oxygen species play an important role in the pathogenesis of acute pancreatitis (AP) in animal models. Data on the oxidant-antioxidant balance in humans are scanty. The present study was undertaken to evaluate the dynamics of changes in the oxidant-antioxidant balance in the early phase of human AP. METHODS 74 consecutive patients with acute biliary pancreatitis (16 with severe, 58 with mild pancreatitis), treated endoscopically, were included in the study. Serum concentrations of sulfhydryl groups (SH; main nonenzymatic antioxidant; 73 patients) and thiobarbituric acid reactive substances (TBARS; markers of reactive oxygen species-mediated tissue damage; 56 patients) were determined on admission and on each of 10 successive days. The analysis comprised the comparison of results in patients with mild and severe outcome of pancreatitis. RESULTS Serum SH dropped by 27%, reaching the trough level on day 4 of hospitalization, whereas serum TBARS rose by 28%, reaching a peak 1 day later. Neither SH nor TBARS returned to initial values at the end of observation. The most dynamic changes in both SH and TBARS concentrations occurred in the first 3 days of hospitalization. The changes were significantly greater in patients with complicated pancreatitis in comparison to patients with mild disease, and were most pronounced in patients who developed infected pancreatic necrosis and who subsequently died. CONCLUSIONS The oxidant-antioxidant balance changes rapidly in the early phase of human AP, confirming the role of oxidative stress in the pathogenesis of AP. The degree of changes correlates with the clinical severity of pancreatitis.